Wireless Broadband Service

ABSTRACT

A fixed broadband wireless data access service providing shared wide-band packet-switched data transport for high speed data access in areas where conventional ADSL service and fiber optic service are unavailable. The wireless data access service is a point-to-multipoint cellular-type network that connects customers to data service providers through the ATM backbone of an existing network. Customers connect to the ATM backbone and data service provider through a cellular grid in which a wireless base station in each cell communicates with the individual customer wireless equipment within its cell site coverage area. The base stations are connected to an ATM backbone switch through wireless and wireline backhaul links. The upstream and downstream bandwidths of the wireless broadband network are engineered in various symmetric and asymmetric configurations to provide a shared packet-switched connection that emulates an uninterrupted, direct wireline ADSL connection. The wireless broadband network employs a data protocol of shared access bandwidth and adaptive asymmetric data rates to support multiuser service sessions by wireless transmission. The wireless broadband network is not network protocol specific and can be applied to wireless asymmetric digital subscriber line service, wireless integrated service digital network over digital subscriber line service, wireless very high bit rate digital subscriber line service, or wireless symmetric or single-line digital subscriber line service.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a divisional application of, and claimspriority to, U.S. patent application Ser. No. 10/879,477, filed Jun. 29,2004 (which will issue as U.S. Pat. No. 7,292,560 on Nov. 6, 2007),which in turn is a continuation application of, and claims priority to,U.S. patent application Ser. No. 09/418,986, filed Oct. 14, 1999 (nowU.S. Pat. No. 6,778,517). The disclosures of the above-referencedpriority applications are hereby incorporated herein by reference inthere entireties as if set forth fully herein.

FIELD OF THE INVENTION

The present invention relates to the field of switched telephony, and inparticular, to wireless digital subscriber services, such as asymmetricdigital subscriber line (ADSL) services, that provide fixed broadbanddata access to remote locations.

BACKGROUND OF THE INVENTION

As electronic communication by businesses and private individuals hasincreased, the demand on network service providers for high speed, i.e.,broadband, data transmission has steadily grown. Originally, serviceproviders attempted to meet such demand with narrow band analog modemsover traditional circuit-switched communication networks. However, thesenetworks unnecessarily consumed resources because they set aside directlines for data transmission even when no voice or data was beingtransmitted. Thus, to utilize network resources more efficiently thanthe circuit-switched communication networks, service providers areincreasingly turning to packet-switched communication and broadband dataservices.

Packet-switched communication utilizes network capacity only whentransferring voice or data. Data is sliced into small packets ofinformation that are transmitted when a circuit is available. Circuitsare not dedicated to certain user applications, as a phone service wouldbe in a circuit-switched network. Instead, circuits remain open andavailable to all on-line users whenever they have data packets totransmit. This allocation strategy keeps lines open and saves networkresources until they are actually needed for communication.

To accomplish this packet-switched broadband data communication,traditional network service providers typically use one of the followingdeployment options: (1) ADSL service using wired landlines (wirelineADSL); (2) integrated fiber in the loop (IFITL); or (3) ISDN, X.25, andother similar deployment services. In the prior art, the network serviceproviders that own these wired telephone lines prefer wireline ADSL todeliver packet-switched data communication in service areas highlyconcentrated with customers because existing wire lines can be used,making ADSL inexpensive relative to the customer revenue produced inconcentrated areas. However, broadband data rates over wire linefacilities are distance dependent and require digital carrier systemsfor support once the length of wire line facilities exceed three milesfrom the central office. In contrast, in less concentrated and remoteareas (e.g., rural areas), the smaller number of potential customerstypically does not offer enough revenue to outweigh the costs to installand maintain the system. In addition, the longer deployment distancesrequire more engineering efforts and capital investment in theimprovement of line qualification to achieve expected transmissionefficiency and quality. Therefore, potential customers in many locationstypically do not have access to wireline ADSL service.

IFITL deployment improves the efficiency and quality of transmissionover greater distances as compared to the wireline ADSL. However, thecost of installing optical fiber lines is very high, such that thelimited numbers of distant potential customers would rarely, if ever,justify the initial investment.

Thus, there remains a need for a supplemental service that extendsexisting packet-switch data networks to less populated and remote areasthat currently have no access. The deployment technique should beeconomical to install and should not suffer from reduced transmissionquality over long distances. Further, the deployment method shouldenable network service providers to furnish remote customers with dataaccess, while still realizing a profit.

SUMMARY OF THE INVENTION

The present invention is a fixed broadband wireless data access servicethat provides broadband packet-switched data transport for high speeddata access. It will be described herein in terms of ADSL, but it couldbe applied in other contexts, such as wireless integrated servicedigital network over digital subscriber line (IDSL), wireless very highbit rate digital subscriber line (VDSL), or wireless symmetric orsingle-line digital subscriber line (SDSL). The following publicationsdescribe the broadband data communications to which this invention canbe applied and are hereby incorporated by reference: (1) Goralski,Walter, SONET: A Guide to Synchronous Optical Networks, McGraw-HillCompanies, May 1997; (2) Stallings, William, ISDN and Broadband ISDNwith Frame Relay and ATM, 4.sup.th Edition, Prentice Hall, Inc., October1998; and (3) Sexton, Mike, and Reid, Andy, Broadband Networking: ATM,SDH, and SONET, Artech House, January 1997. Additionally, the presentinvention will be described herein in terms of an asynchronous transfermode (ATM) network protocol, but should be understood to apply to otherpacket-switched data protocols, such as Internet Protocol (IP) over theair.

Based on asynchronous transfer mode technology, wireless ADSLsupplements an existing packet-switched data network to extend highspeed data services to remote locations. The wireless ADSL network is apoint-to-multipoint cellular-type network that connects to a dataservice provider (e.g., an internet service provider or corporate localaccess network) through an existing ATM regional broadband network (alsoreferred to as a backbone network). The following publications describethe ADSL and ATM technology and are hereby incorporated by reference:(1) Goralski, Walter, ADSL and DSL Technologies, McGraw-Hill Series onComputer Communications, 1998, ISBN 0-07-024679-3; and (2) ADSLDocuments of ITU Standard, T1E1.413. Also incorporated by reference,similar publications describing IDSL, VDSL, and SDSL are: (1) Starr,Cioffi, and Silverman, Understanding Digital Subscriber Line Technology,Prentice Hall 1999, ISBN 0137805454; (2) Roberts, R., VDSL Out-of-BandSpectral Roll-off: FCC Part 15 Compliance Based Upon Flat-PairDistribution-Cable Radiation, ANSI T1E1.4/97-244, Minneapolis, Minn.,September 1997; and (3) Cioffi, John, VDSL System Requirements Document,ANSI Contribution T1E1.4/98-043R3, June 1998. In addition, U.S. Pat. No.5,479,447, issued Dec. 26, 1995 to Chow et al., discloses a method andapparatus for adaptive, variable-bandwidth, high speed data transmissionof a multicarrier signal over digital subscriber lines, and is herebyincorporated by reference.

To support multiuser service sessions by wireless transmission, thepresent invention employs a data protocol of shared access bandwidthwith adaptive asymmetric data rates. The strategy of sharing, bandwidthby time allows several customers to simultaneously interface with awireless transmitter/receiver connected to the ATM backbone.Additionally, adaptive asymmetric data rate protocols optimize thecommunication between the multiple customers and the wirelesstransmitter/receiver. The asymmetric data rate protocol tailors the datastreams between the customer and wireless transmitter/receiver toaccommodate changes in the amount of data that must be transmitted.Communication travels back and forth between the customer equipment andthe wireless transmitter/receiver such that one side transmits data andthen listens for transmissions by the other side. As a result, thewireless data protocol of the present invention fully integrates thewireless multiuser high speed data access service with the wirelineregional broadband network and the connected data service providers.

As shown in FIG. 1, the present invention builds upon the ATM switch ofan existing regional broadband network. Base stations located nearest tothe ATM switch are connected through wireline or wireless backhaul linksto the ATM switch (FIG. 1 shows wireline backhaul links, but wirelessbackhaul links could also be used). A base station includes“trans/ceiver radio”, “RF channel combiner”, and/or any kind of filters.Backhaul links are the transmission facilities, like transport trunkscarrying concentrated user data and network signaling, that support theduplex communications between customer ends and a central location suchas a switch or service provider's network. Each base station, consistingof wireless transmission equipment, is centrally located in a networkcell to provide shared high speed wireless access to each customercovered by the same transmitter/receiver antenna at the cell hub. Thecustomers within the cells each have wireless customer equipment forcommunicating with the base station equipment. The base stations areconnected to the nearest ATM switch through backhaul links that can beradio-frequency (RF) backhaul links, land line backhaul links, or acombination of the two. Cells are linked together on backhaul facilitiesto the ATM switch. The layers of linked cells produce a network ofintegrated broadband data service that uses wireless technology todeliver high speed data access to previously unreachable areas.

Also connected to the ATM switch is a network management system (NMS)that provides a network view of all its managed elements. The NMScontrols and monitors the end-to-end operations of the wireless ADSLnetwork, such operations including network creation, flow-throughprovisioning, fault and performance management, capacity and trafficmanagement, accounting management, and security management.

The present invention uses a data management strategy that providescustomers with seamless data transfer. Although customers within a cellshare packet-switched data connections over the air, the wireless ADSLnetwork provides each customer with an individual permanent virtualconnection that provides continuous high speed data access. In thepreferred embodiment, the present invention supports a wide range ofpacket-switched data services, e.g., internet access, on-line webbrowsing, wireless VoIP (voice over internet protocol), wireless voiceservice, interactive video services, nomadic wireless data access, andbroadband mobile data access.

To provide uninterrupted service, the downstream bandwidth from thenetwork to the customer or the upstream bandwidth from the customer tothe network can be engineered in various symmetric and asymmetricconfigurations. In the preferred embodiment, the particular data trafficmanagement configuration is tailored to meet the needs of individualcustomers. The base stations communicate with customer radio equipmentthat links to an Ethernet or ATM interface on the customer's network,depending on the interface required by the customer's network model. Thecustomer radios in each cell share the same down-link wireless datachannel, and send user traffic data back to the base station. The modeof transmission from a base station to customer radios ispoint-to-multipoint, while the mode of transmission from an individualcustomer radio to a base station is point-to-point.

Accordingly, it is an object of the present invention to provideeconomic high speed data access to customers in locations where wirelineADSL and IFITL service is not available.

It is another object of the present invention to provide a wide range ofpacket-switched data services to multiple consumers using sharedwireless packet-switched data connections.

These and other objects of the present invention are described ingreater detail in the detailed description of the invention, theappended drawings, and the attached claims.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of the wireless ADSL network.

FIG. 2 is a schematic diagram of the service and network managementsystems of the wireless ADSL network.

FIG. 3 is a schematic diagram of the wireless ADSL data networkarchitecture.

FIG. 4 a is a schematic diagram of a customer premise networkarchitecture for a customer with a single personal computer.

FIG. 4 b is a schematic diagram of a local area network (LAN)architecture in a customer premise.

DETAILED DESCRIPTION OF THE INVENTION

Referring to FIG. 1, the present invention comprises four primarycomponents: a regional broadband network 100, a network managementsystem 102, cell hub equipment 104, and customer equipment 106. Regionalbroadband network 100 is an existing packet-switched communicationsnetwork that interfaces with data service providers, e.g., an internetservice provider server 120 or a corporate intranet server 122. Throughan ATM switch 108, regional broadband network 100 connects to NMS 102.NMS 102 monitors and controls all network communications. Also throughATM switch 108, regional broadband network 100 connects to cell hubequipment 104 through either wired landlines or wireless links. Cell hubequipment 104 is distributed throughout a service region in a gridpattern, in which each set of cell hub equipment services a cell sitecoverage area 110. Cell hub equipment 104 at each cell site locationconsists of one or more base stations that communicate directly withindividual customer equipment 106 located within the cell site coveragearea 110. Both cell hub equipment 104 and customer equipment 106comprise radio-frequency transmitters and receivers. Customer equipment106 also includes links to local area networks and data terminals, suchas personal computers.

Communication through the wireless ADSL network originates at theregional broadband network 100 and traverses the following path: fromregional broadband network 100 to ATM switch 108, from ATM switch 108 tocell hub equipment 104, and from cell hub equipment 104 to customerequipment 106. Within customer equipment 106, communication terminatesat a personal computer inside the customer premises (and, in the case ofmultiple users within one customer premises, flows through a local areanetwork before terminating at the individual computers). Data flows fromend to end in both directions along this communication path.Additionally, although the described path includes only one layer ofcell sites, it would be apparent to one skilled in the art that multiplelayers of cell hub equipment may exist by which cell sites can be linkedsuch that the data from a distant cell site may travel from cell hubequipment to cell hub equipment before reaching ATM switch 108 andregional broadband network 100. An example of this multiple layercommunication is shown schematically in FIG. 1.

To properly integrate the wireless data transfer with the existingwireline ADSL network, the present invention incorporates a dataprotocol that splits bandwidth among individual customer equipment 106in a cell and varies the data rates between customer equipment 106 andcell hub equipment 104. To provide simultaneous access to several users,the bandwidth is divided such that one side transmits and listens fortransmission from the other side. The bandwidth sharing is accomplishedby one of several technologies used to distinguish multiple accessesover a finite frequency spectrum, e.g., Time Division Multiplex, TimeDivision Multiple Access, Frequency Division Multiple Access, or CodeDivision Multiple Access.

The transmitted data rate is asymmetric and adaptive such that the ratioof the upstream and downstream data rate is dynamically updated. Unlikewireline ADSL, the wireless ADSL adjusts data rates to accommodatevarying amounts of traffic data on demand. Software provisioned on cellhub equipment 104 automatically controls data traffic between cell hubequipment 104 and customer equipment 106, selecting data rates suitablefor the traffic demand and the capacity of the cell hub equipment 104.Controlling the data rate improves the capacity utilization between thewireless portion and existing wireline portion of the present invention.

The data protocol facilitates shared packet-switched communication overthe air. The typical number of customer equipment 106 serviced by asingle station of cell hub equipment 104 depends on the radio coverage,number of sectored radios, and the bandwidth capacity of each sectoredradio for the transmitter/receiver at the single station of cell hubequipment 104. For radio coverage, the higher the antenna is positionedwith the higher the power supplied by cell hub equipment 104 and thehigher the density of customer equipment 106, the larger the possiblenumber of connected customer equipment 106. For bandwidth capacity, thetotal number of customers within radio coverage depends on the minimumdata bandwidth guaranteed to each customer, e.g., if 20 Mbps have beenallocated for a cell site with 20 customers, a service provider canguarantee 1 Mbps to each customer (the service provider could alsoincrease the number of customers by factoring in the minimum number ofnonusers at any given time and adding that number to the total number ofserviceable customers).

System Components

Turning to the individual components of the wireless ADSL networks, thefollowing sections describe the specific structure of the networkcomponents:

Regional Broadband Network

Regional broadband network 100 consists of high-bit-rate backhaultransport facilities and an existing ATM data network. These twoelements interface cell sites to individual networks of network serviceproviders. The high-bit-rate backhaul facilities connect the wirelessADSL base stations to ATM switch 108 in the ATM data network. In thepreferred embodiment, the backhaul facilities are either DS-3 or OC-3lines and are traffic engineered to implement service level agreementsto meet the needs of the customers. The service level agreementsdescribe selected parameter sets, which form different classes ofservices. For example, reserved data bandwidth is one of the keyparameters in the agreements. The term “traffic engineering” refers tothe method of dimensioning telecommunications equipment to provideservice to customers at a defined quality of service.

As part of regional broadband network 100, the existing ATM data networkis an interconnection broadband packet data network. An interconnectionbroadband packet-data network is a set of provisioned high speed datatransmission facilities between networks or systems. In the preferredembodiment of the present invention, the ATM data network comprisesCarrier Class ATM switches that deliver broadband services to bothresidential and small business customers.

Network Management System

Network management system (NMS) 102 is connected to ATM switch 108 ofregional broadband network 100. NMS 102 is a comprehensive system formonitoring, controlling, and managing the data communication fromregional broadband network 100 to customer equipment 106 via cell hubequipment 104. Providing end-to-end and uniform operation supportcapabilities, NMS 102 enables network creation, flow-throughprovisioning, fault collection and correlation, capacity and trafficmanagement, performance management, and accounting and securitymanagement.

In a preferred embodiment of the present invention, NMS 102 uses aTelecommunications Management Network (TMN) layered architecture toinvoke Operation Support Systems, i.e., methods and procedures thatdirectly support the daily operation of the network infrastructure. Thefollowing publication describes the TMN architecture and is herebyincorporated by reference: ITU-T (International TelecommunicationsUnion-Telecommunications) Recommendation M.3010, “Principles for aTelecommunications Management Network,” October 1992. As shown in FIG.2, NMS 102 operates as part of a service management system 200 thatfacilitates the provisioning and administration of service data. NMS 102oversees all element management systems (EMSs) 202. The EMSs 202 manageall related network elements 204 and interact with NTMS 102 through anegotiated interface. In the preferred embodiment, the negotiatedinterface is a Common Object Request Broker Architecture (CORBA) basedinterface. The interface is proposed in wireless ADSL, and is the sameinterface that is implemented in the conventional wireline ADSL. Apreferable network layout of Access EMS 206 and ATM EMS 208 is shown inFIG. 2.

In the preferred embodiment, an individual EMS provides several highlevel functions within NMS 102. First, the EMS furnishes to NMS 102 allrelated information required for NMS 102 to accomplish the end-to-endoperations described above. Second, the EMS is configured to receive andterminate NMS messages, i.e., the NMS/EMS interface must not be a“pass-through” interface. Thus, in response to NMS messages targeted andterminated at the EMS, the EMS takes appropriate action and reports backto NMS 102. The EMS manages detailed information from each NetworkElement within its domain and sends only appropriate information to NMS102 as a part of the negotiated interface. Further, the EMS manages itsrespective Network Elements on a subnetwork basis (as defined in thecontext of the M4 Model in the ATM Forum), i.e., the EMS has the abilityto manage a subgroup of network elements as if the network elements wereone network element.

The individual elements of network elements 204 are defined as follows.Access radio is the radio at the based station, which is a radiofrequency transmitter/receiver that communicates with consumer radios.In general, access radios are sectored radios (an Omni access radio is aspecial case). Access radios give customer access to the broadbandnetwork data pipe (trunk). In the reverse direction, the accessconcentrator distributes the data traffic among proper access radiosthat relay the data to consumer ends.

A third high level function of the EMS is the support of transmission ofthe auto-discovered network element information from the EMS domain toNMS 102, e.g., new cards in the base station equipment. Theauto-discovered (AD) function automatically detects any element underthe control of the EMS that is newly configured and/or newly out ofservice, reports the existence of the new element, and updates itsdatabase to monitor and control the new equipment and configuration.

As a final high level function, the EMS provides a graphical userinterface at the EMS level to manage the installation of networkelements. The graphical user interface is preferably a web graphicaluser interface.

Cell Hub Equipment

Cell hub equipment 104 is located at one base station, which isconnected to an omni-directional antenna or a set of sectored antenna(s)centrally located in a cell site. The antenna(s) is/are positioned ontop of a pole, tree, tower, or other tall structure of height rangingfrom 25-150 feet, depending on whether microcells or macrocells aredeployed. However, for access by mobile customers, macrocells should beconsidered. Preferably, the service area of each cell covers ⅓ to 3miles in radius.

The base station antennas in each cell communicate with customer unitsby wireless transmission. Preferably, transmission power is high enoughto provide adequate service coverage for all customers in the cell,within compliance with FCC regulations. Further, the transmission isdigital, using programmable multilevel radio-frequency (RF) modulationschemes. Because of the asymmetric nature of ADSL traffic, the RFchannel duplex method is preferably time division duplex; however,frequency division duplex is an acceptable alternative. Also, because ofthe asymmetric nature of ADSL traffic, the channel access method ispreferably time division multiple access; however, code divisionmultiple access is also possible.

Cell hub equipment 104 also includes connection management equipment andpacket-switching equipment. The connection management equipment managesboth the base stations and the backhaul connections and is responsiblefor: (1) customer equipment authentication (determining if customer isan approved subscriber); (2) configuration and control of customerequipment, base station, and backhaul communication; and (3) remote ATMsignaling support. The packet-switching equipment aggregates trafficfrom individual base station antennas to the high speed data backhaulfacility and distributes the traffic in the reverse direction.

Customer Equipment

To complete the delivery of high speed data access to the customer,customer equipment 106 is installed at businesses or residences tocommunicate with the wireless cell hub equipment 104. As the final partof the communication path, customer equipment 106 comprises an outsidewireless transmitter/receiver radio, wire cabling from the wirelesstransmitter/receiver radio to inside the customer premises, a networkinterface card connected to the cabling, and a personal computerconnected to the network interface card. (If there are multiplecomputers within a single customer premises, the cabling connects to alocal area network and each computer has a separate network interfacecard.). The wireless transmitter/receiver radio is preferably installedat a fixed location on the roof or side of a customer's premises at aheight sufficient for line-of-sight transmission to cell hub equipment104. The cabling joins the wireless transmitter/receiver radio to thelocal area network or individual personal computer within the customer'spremises by an appropriate connection, e.g., 10Base-T, 100Base-T, orATM25. At each personal computer, a network interface card, e.g., anEthernet or ATM network interface card, is installed. The networkinterface card attaches to either a local area network communicationsdevice (e.g., a hub) or directly to the wireless transmitter/receiverradio.

The wireless connection and transport from customer equipment 106 tocell hub equipment 104 employs ATM packet-switching technology and isshared by multiple users covered by the same wirelesstransmitter/receiver radio installed at base station of cell hubequipment 104. For a local area network that supports multiple personalcomputers, multi-user traffic from the local access network shares thecustomer equipment's total access capacity. Within the coverage of asingle base station, multi-user traffic data from many customers'equipment share the total bandwidth of a RF channel. The RF transmissionfrom customer equipment 106 supports communications with the basestations of cell hub equipment 104. The total radio bandwidth of the RFchannel is managed by connection management equipment in cell hubequipment 104.

Communication Protocol

The system components described above form a wireless ADSL data networkarchitecture as shown in FIG. 3 that provides a high speed wireless datainterface for delivering differentiated broadband data services tocustomers via a local area network infrastructure. The wireless ADSLsystem uses the RF spectrum for wireless transmission, and in thepreferred embodiment, uses the most easily accessible spectrum bands,e.g., unlicensed bands such as the Industrial, Scientific, and Medicalbands and the National Information Infrastructure band. Alternatively,the wireless ADSL network could use licensed bands such as the WirelessCommunications Services band and the Multi-channel MultipointDistribution Service band.

The communication protocol used in the access network and regionalbroadband network portions of the wireless ADSL data servicearchitecture is shown in FIG. 3. In a preferred embodiment,Point-to-Multipoint Protocol (PMPP)/ATM protocol is used as thetransport protocol for data services across the U interface into thecustomer premises, and Point-to-Point Protocol (PPP)/ATM protocol isused as the transport protocol for data services from the customerpremises to the access concentrator 300. These transport protocolspreserve the network interfaces and functions seen by customers whenaccessing remote applications and Radius services. Radius services areremote authentication dial-in user services that include authenticationof users and accounting for billing purposes. The following publicationdescribes Radius services and is hereby incorporated by reference: IETFDraft on Layer Two Tunneling Protocol “L2TP”, October 1998. Thus, a userperceives that he or she is directly linked to a network serviceprovider, although in reality the user is sharing packet-switched dataaccess over a distributed network.

Within regional broadband network 100, but before ATM switch 108, anaccess concentrator 300 aggregates all of the regional customer datatraffic into one “tunnel” and aggregates the Layer 2 Access Concentrator(LAC) over one Permanent Virtual Circuit (PVC). The regional customerdata traffic originates from multiple sets of customer equipment 106 andflows through cell hub equipment (represented in FIG. 3 as access radio302) to access concentrator 300. After access concentrator 300, theaggregated data is then transported through the ATM switch 108 to thenetwork service provider network 304. Although in FIG. 3 PPP/L2TP/ATM isshown as the transport protocol at G, a different protocol may be used,depending on the needs of the network service provider equipment andbusiness interface. It is important to note that the access concentrator300 at V aggregates services from many different access technologiesinto one or more physical and/or logical interfaces. Thus, for example,wireline ADSL, dial-up, and T-1 could all be aggregated into the sameinterface at the access concentrator 300. However, the preferredembodiment of the protocol stack for current and future accesstechnologies is PPP/ATM. PPP/ATM is preferred because of its currentavailability and because its use preserves the network interfaces andfunctions seen by the user. Using PPP protocol hides from the user thefact that a distributed network is being used to connect to the serviceprovider. With the PPP protocol, the user perceives a single networkconnection rather than a collection of independent physical links.

As shown in FIG. 4 a, at the customer premises, the communicationprotocol maps point-to-point sessions from a customer's personalcomputer 410 to the wireless transmitter/receiver radio 414. Thepreferred embodiment of the present invention uses PPP/ATM protocolwithin the customer network to conform to typical industry practice. Forcustomers with single personal computers, an ATM25 network interfacecard 412 would be used to connect to wireless transmitter/receiver radio414. For customers with multiple devices within the customer network, asmall ATM switch/router is inserted between personal computer 410 andwireless transmitter/receiver radio 414.

In the case of traditional Ethernet local area networks, alternativenetworking technology is employed to map point-to-point sessions from acustomer's personal computer to the wireless transmitter/receiver radio.An example of this alternative architecture is shown in FIG. 4 b. Thearchitecture uses point-to-point protocol over the Ethernet in acommunication from a local area network 420. In each personal computer,one Ethernet card is installed. The data traffic from an individualpersonal computer through its Ethernet network interface card 422 isaggregated at the Ethernet network interface card 422 and forwarded to awireless transmitter/receiver radio 424.

The communication protocols described above enable the present inventionto emulate wireline ADSL as perceived by the customer. Specifically, thecommunication protocols create several aspects of network transparency,as a result of which the customer perceives that she has a directconnection with the network service provider, rather than a sharedpacket-switched connection. The individual aspects of this networktransparency are as follows:

1) Access Transparency: The wireless ADSL network protocol supportsmultiple, independent, and simultaneous point-to-point sessions betweencustomer personal computers on customer premises' local area networksand network service providers. Further, the network's point-to-pointtransport is not impaired among multiple layer-3 protocols.

2) Class-of-Service Transparency: The data service architecture supportsindependent classes of service for each user session, which enableslocal area network users at customer premises to subscribe to adifferentiated grade of service from service providers. Further, thedata service architecture supports a mechanism of Quality of Servicemapping between point-to-point session and ATM virtual channels.

3) Address Transparency: Specifically, the data service architectureenables customer premise local area network users to access serviceproviders by using either a registered or private network address bytraditional or virtual dial-up.

4) Scaling Transparency: Using the communication protocol, the dataservice architecture does not significantly limit the number of customerlines in the access network nor limit the number of concurrentpoint-to-point sessions established to any one network service provider.

5) Authentication, Authorization, and Accounting: Specifically, the dataservice architecture preserves the authentication, authorization, andaccounting functions of each point-to-point session.

6) Incoming Calls: Data architecture does not preclude the support ofincoming calls for either point-to-point sessions or ATM SwitchedVirtual Connections.

Advantages

The present invention offers several advantages in extending ADSLservice to remote locations. Because the deployment strategy builds uponan existing regional broadband network, it is not necessary to investlarge sums of money in developing a regional broadband network. Inaddition, existing regional broadband networks may not be fully loaded,such that the addition of the wireless ADSL service fully utilizesnetwork resources.

Another advantage of the present invention is the ability to run IPprotocol at the customer premises while running ATM protocol over theair and over the backbone network. This allows the customers to use theIP local area network interface cards that they already have, instead ofhaving to purchase additional ATM interface cards.

The network architecture of the present invention will also support manydifferent future vertical packet-switched data services, includingwireless voice over internet protocol (VoIP), wireless voicetelecommunications over ATM (VToA), packet-switched data return path forinteractive TV or video, nomadic data access through wirelesstransmission, and broadband mobile data access.

Another advantage of the present invention is its ability to transmitover long distances without reduced transmission quality. In wirelessADSL, loop qualification is unnecessary and the absence of hardconnections (e.g., bridge taps) keeps transmission quality high.

Finally, the network strategy of the present invention offers asignificant advantage in its breadth of application. In particular, thenetwork architecture and protocols are not limited to specific vendors,services, radio spectrums, network protocols, or wireless accesstechnologies.

With regard to network protocols, the preferred embodiment describes anATM implementation for purposes of illustration and should not beconstrued to be limited to the ATM network protocol. Rather, it shouldbe noted that the implementation of wireless ADSL is not networkprotocol specific and that the preferred embodiment is compatible withother wireless ADSL implementations based on packet-switched dataprotocol such as Internet Protocol (IP) over the air. The ATM networkprotocol was chosen to illustrate the preferred embodiment simplybecause of the current availability of existing ATM backbone networksand the high level of familiarity those skilled in the art hold for thecurrent ATM networks.

With regard to wireless access technologies, the preferred embodimentdescribes a wireless ADSL service for the purpose of illustration andshould not be construed to be limited to wireless ADSL. The disclosedarchitecture could also be applied to wireless integrated servicedigital network over digital subscriber line (IDSL), to wireless veryhigh bit rate digital subscriber line (VDSL), or to wireless symmetricor single-line digital subscriber line (SDSL).

The foregoing disclosure of embodiments of the present invention hasbeen presented for purposes of illustration and description. It is notintended to be exhaustive or to limit the invention to the precise formsdisclosed. Many variations and modifications of the embodimentsdescribed herein will be obvious to one of ordinary skill in the art inlight of the above disclosure. The scope of the invention is to bedefined only by the claims appended hereto, and by their equivalents.

1. A communications network, comprising: a broadband network; aplurality of primary cell hub equipments linked to the broadbandnetwork; a plurality of secondary cell hub equipments in communicationswith respective of the plurality of primary cell hub equipments bywireless backhaul communications links; a plurality of customerequipments in communication with respective of the plurality ofsecondary cell hub equipments by wireless backhaul communications links;and a network management system that is configured to controlcommunication between the broadband network and the plurality ofcustomer equipments.
 2. The communications network of claim 1, whereinthe broadband network comprises a packet-switched broadband network. 3.The communications network of claim 2, wherein the packet-switchedbroadband network supports an internet protocol (IP) over the airnetwork protocol.
 4. The communications network of claim 2, wherein thepacket-switched broadband network Supports an asynchronous transfer mode(ATM) network protocol.
 5. The communications network of claim 1,wherein the radio-frequency backhaul communications links between theplurality of customer equipments and the secondary cell hub equipmentsuse shared packet-switched data transport with a shared access bandwidthwith adaptive asymmetric data rates.
 6. The communications network ofclaim 1, wherein a point-to-point, point-to-multipoint and asynchronoustransfer mode protocol governs a communication between the broadbandnetwork and the plurality of customer equipments.
 7. The communicationsnetwork of claim 1, wherein the wireless backhaul communications linksbetween the plurality of customer equipments and the plurality ofsecondary cell hub equipments comprises wireless asynchronous digitalsubscriber line service communication links.